Contents lists available at ScienceDirect Applied Soil Ecology journal homepage: www.elsevier.com/locate/apsoil Beetle and maize yield response to plant residue application and manual weeding under two tillage systems in northern Zimbabwe Nilton Mashavakure a, ⁎ , Arnold B. Mashingaidze a , Robert Musundire a , Edson Gandiwa b , Christian Thierfelder c , Victor K. Muposhi b a School of Agricultural Sciences and Technology, Chinhoyi University of Technology, Private Bag 7724, Chinhoyi, Zimbabwe b School of Wildlife, Ecology and Conservation, Chinhoyi University of Technology, Private Bag 7724, Chinhoyi, Zimbabwe c CIMMYT, P.O. Box MP 163, Mount Pleasant, Harare, Zimbabwe ARTICLE INFO Keywords: No-tillage Plant residue application Soil beetles Weeding intensity ABSTRACT Surface-dwelling beetles are among some benefcial arthropods inhabiting agricultural felds, but they can be negatively afected by agricultural practices. In this study, we investigated the efects of plant residue application rates and weeding intensity on surface-dwelling beetle communities and maize yield under two tillage systems, using a long-term experiment at Chinhoyi University of Technology experimental farm, northern Zimbabwe. The experiment was established in December 2012 as a split-split plot in randomized complete blocks replicated three times, and data for our study were collected during two growing seasons (2013/14 and 2014/15). Beetle species such as Abacetus spp., Ancophthalmus oncotipes and Renatiella reticulata showed increased while Dromica limpompoipana had decreased abundances under no- relative to conventional tillage. Abundances of Zophosis boei decreased while those of Gonocephalum simplex, R. reticulata, Stenethmus tentyriniformis and Trachynotus re- ticulatus increased under plant residue application. During the third growing season of annual runs of the treatments, maize yield was least (4620 kg ha −1 ) in plots without plant residues and highest (10,978 kg ha −1 ) in plots treated with 8 t ha −1 of plant residues. During the same growing season, maize grain yield was positively correlated with total abundance of beetles and those of R.reticulata, S.tentyriniformis and T.reticulatus. The efect of tillage system and weeding intensity on beetle abundance and maize grain yield under the environmental conditions of this specifc study was minimal, but plant residue application promoted beetle species abundance while increasing maize grain yield. 1. Introduction Ground surface dwelling beetles are among some benefcial ar- thropods in agroecosystems, having potential for providing services such as pest predation, weed herbivory, detritivory and weed seed granivory (Knapp and Řezáč, 2015). Detritivorous beetles aid in de- composition of plant residues into smaller substrates for further breakdown by other organisms, thus improving the net mineralisation and nutrient retention in the soil. A considerable number of herbivorous beetles are biological weed control agents (Gurr and You, 2016). Moreover, some granivorous beetles are important in reducing the weed seed bank and therefore reduce crop-weed competition in crop- ping systems. In a review, Kromp (1999) showed that some predatory Carabidae are important in biological pest control in sustainable agroecosystems of the temperate Northern hemisphere. Most intensively managed agroecosystems usually focus on maximising agricultural production but there is minimum consideration of biodiversity conservation in these systems. Intensive farming systems cause decline in abundance and diversity of beetle communities and their associated benefcial services in arable lands (Barberi et al., 2010; Knapp and Řezáč, 2015). For the less intensively managed agroeco- systems, arthropod diversity has been reported to be high (Soane et al., 2012). These farming systems can conserve biodiversity and enhance benefcial ecological processes in cropping systems including nutrient cycling and biological pest control. Moreover, high and sustainable crop yields have been reported in such agroecosystems (Thierfelder and Wall, 2012; Thierfelder et al., 2015; Williams et al., 2018). Besides physical injury to beetle individuals, mechanical tillage destroys nesting, overwintering and refuge sites and therefore con- tributes to low beetle abundance and diversity in conventionally tilled agroecosystems (Hofmann et al., 2009). Plant residues act as refuge sites, provide food resources for detritivorous species and also conserve https://doi.org/10.1016/j.apsoil.2019.07.016 Received 7 February 2019; Received in revised form 22 July 2019; Accepted 24 July 2019 ⁎ Corresponding author. E-mail address: nmashavkure@cut.ac.zw (N. Mashavakure). Applied Soil Ecology 144 (2019) 139–146 0929-1393/ © 2019 Elsevier B.V. All rights reserved. T